Phase 2 scaffold: mitra online status & pairing logic

Add mitra online/offline status with heartbeat-based auto-offline,
customer-mitra pairing via Valkey pub/sub blast, session management,
and control center dashboard with real-time stats.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

CLAUDE.md

@@ -30,7 +30,8 @@ Mental health chat platform connecting clients (users seeking support) with trai
 - **Control center is internal-only** — never expose its API routes to the public internet; protected via Nginx allow/deny + VPN
 - **Firebase Auth** tokens are verified on Fastify via JWT — user data lives in PostgreSQL, linked by Firebase UID
 - **Horizontal scaling** (Cloud Run) handles load — do not split into microservices prematurely
-- **Real-time features** (chat) are deferred to requirements phase
+- **Real-time features** use Valkey pub/sub for in-app events; FCM push notifications planned for next phase
+- **Pairing** uses blast-to-all-available-mitras with first-come-first-served acceptance
 
 ## Current Progress
 
@@ -40,7 +41,12 @@ Mental health chat platform connecting clients (users seeking support) with trai
   - mitra_app: OTP-only login
   - control_center: email/password login, mitra management, user management, anonymity settings
   - Docs: `requirement/phase1-plan.md`, `requirement/phase1-api-contract.md`, `requirement/client_app_mockup.html`
-- **Phase 2 (Sessions, Chat, Payments)** — not yet started, requirements not yet written
+- **Phase 2 (Mitra Online Status & Pairing)** — fully scaffolded
+  - Backend: Valkey pub/sub, mitra online/offline status + heartbeat + auto-offline, pairing service, session management, dashboard stats
+  - client_app: "Mulai Curhat" CTA, searching/found/no-bestie/session-active screens, PairingBloc
+  - mitra_app: online/offline toggle, heartbeat + lifecycle handling, incoming request notification, active sessions screen
+  - control_center: dashboard (auto-refresh), max customers per mitra config, session management + reroute, mitra online logs
+  - Docs: `requirement/phase2.md`, `requirement/phase2-plan.md`
 
 ## Domain Concepts